Bag delivery mechanism for bag closing machines



June 15, 1954 H. v. KINDSETH ETAL BAG DELIVERY MECHANISM FOR BAG CLOSING MACHINES Filed Dec. 5, 1951 4 she'ts-sheet 1 June 1954 H. v. KINDSETH ETAL 2,681,133

BAG DELIVERY MECHANISM FOR BAG CLOSING MACHINES Filed Dec. 5, 19,51

4 sheets sheet 2 June 1954 H. v. KINDSETH ETAL 2,631,133

BAG DELIVERY MECHANISM FOR BAG CLOSING MACHINES Filed Dec. 5, 1951 4 Sheets-Sheet 3 if J f5 42 June 1954 H. v. KINDSETH. ETAL BAG DELIVERY'MECHANISM FOR BAG CLOSING MACHINES FiledDec. 5, 1951 v 4 Sh ets-Sheet 4 6? IN V EN TORS HAFUZQ I! Al/VDSETH F/PA/VA l Ha /(m4: BY Wm Patented June 15, 1954 BAG DELIVERY MECHANISM FOR BAG CLOSING MACHINES Harold V. Kindseth and Frank L. Hopkins, Minneapolis, Minn., assignors to Bemis Bro. Bag 00., Minneapolis, Minn., a corporation of Missouri Application December 5, 1951, Serial No. 259,994

9 Claims.

Our invention relates generally to improvements in bag closing machines and more particularly to mechanism for handling filled bags after closing and sealing thereof.

More specifically, our invention is in the nature of an improvement on certain of the structures disclosed in the United States Letters Patent No. 1,868,686 and No. 1,989, 17 1, granted to Daniel Belcher.

In bag closing and sealing machines of the character exemplified in the United States patents above identified, the filled bags are generally supported and held in rotary bag-holding devices during the closing and sealing of the bags, after which the sealed bags are deposited on conveyors for transport to points remote from the bagholding devices.

In the machine of the present invention, the closed and sealed bags are received from the bagholding device by a conveyor which delivers the sealed bags to a second conveyor which, in turn, carries the bags at a predetermined speed away from the machine to a suitable place for packing the bags in cartons or otherwise disposing of the same. The speed of conveying movement of the second conveyor is preferably less than the normal speed of the first conveyor for the purpose of allowing sufiicient time for the adhesive used in sealing the bags to become dry, or at least set, before further handling. The normal speed of the first conveyor for the sealed bag is sufficient to move the bags out of reach of the moving bag holder once the bag is delivered thereto, in order to prevent the filled bag from being jostled or tipped by the bag-holding device during its continued movement. When the bag approaches the station at which it is transferred to the second conveyor, the difference between the normal speed of the first conveyor and that of the second conveyor is often sufiicient to cause the bag to upset when the same is transferred to the second conveyor. An important object of our invention is, therefore, the provision of means for moving the first conveyor at a given speed when the conveyor receives a closed and sealed bag from the bag-holding device and at a different speed when the sealed bag approaches the station where it is transferred to the second conveyor.

Another object of our invention is the provision of novel speed change mechanism and automatic control means therefor, said control means being operative to cause changes in output speed of the speed change mechanism.

Another object of our invention is the provision 2 of a delivery conveyor and operating mechanism therefor, in machines of this character, which is relatively simple and inexpensive to produce, which is efiicient in operation, and which is rugged in construction and durable in use.

Other highly important objects and advantages of our invention will become apparent from the following detailed specification, appended claims, and attached drawings.

Referring to the drawings which illustrate the invention and in which like characters indicate like parts throughout the several views:

Fig. 1 is a view in side elevation of a closing and sealing mechanism for filled bags incorporating our invention;

Fig. 2 is an enlarged fragmentary view in side elevation of certain operating elements of the machine of our invention, some parts being broken away and some parts shown in section;

Fig. 3 is a top plan view of a portion of the delivery mechanism of the machine illustrated in Figs. 1 and 2;

Fig. 4 is a fragmentary view in side elevation of the delivery mechanism of our invention, some parts being broken away;

Fig. 5 is an enlarged fragmentary view in side elevation of the speed change mechanism of our invention;

Fig. 6 is an axial section taken substantially on the line 6-43 of Fig. 5;

Fig. '7 is a fragmentary view in plan and partly in section taken substantially on the line 11 of Fig. 6;

Fig. 8 is a detail in section, taken substantially on the line 83 of Fig. 6; and

Fig. 9 is a transverse section taken on the line 3-4] of Fig. 6 on a slightly reduced scale.

Referring with greater detail to the drawings, a frame structure I is shown as supporting a conveyor mechanism 2 which may be assumed to be of the endless belt variety and which comprises a portion of means for delivering open-topped filled movable bags 3 to a movable bag-holding member indicated in its entirety by the numeral t. The said movable member includes a disc-like rotor 5 having mounted thereon a plurality of circumferentially spaced plate-like side wall forming members 6 which cooperate therewith to form bag-holding compartments 1 each containing one of the bags 3. The compartments l are further defined by stationary end wall forming elements 8 and movable wall elements 9, see Fig. 2. The movable element 4 is journalled for rotation on a shaft [0 which extends transversely of the frame I and is secured at its opposite ends therein. With further reference to Fig. 2, it will be seen that the stationary cam H engages a plurality of cam follower rollers I2 one each associated with one of the plate-like compartment walls ii whereby said Walls 8 are movable laterally to clamp and release a bag therebetween and the opposite side wall formed by the rotor 5. Coil tension springs l3 bias the cam followers 52 toward engagement with the cam I l.

The movable member 5 has mounted fast thereon a gear It which has meshing engagement with a pinnion fast on a drive shaft !6 journalled in suitable bearings H in the frame i, one of said bearings being shown in Fig. 6. The drive shaft 16 is driven from a suitable source of power such as an electric motor it through suitable transmission mechanism such as an endless drive belt !9 running over suitable pulleys 20 and 2! one on the shaft of the motor is and the other on the input shaft of a conventional speed reducer 22. A second endless drive belt or chain 23 may be assumed to run over suitable pulleys or sprockets, not shown but mounted one each on the output shaft of the speed reducer 22 and the drive shaft Hi.

When each bag 3 is delivered to a compartment 1 in the movable member l, continued rotation of the movable member l will place the bag in position wherein suitable adhesive applied to the upper end thereof, said upper end being then folded to a closed and sealed position. One of the top-folding mechanisms is shown in Fig. l and is indicated in its entirety at 24. As the movable member 4 rotates, the closed tops of the bags are successively brought into engagement with an arcuate plate-like stationary member 25, see Fig. 2, which maintains the tops in a closed position during the latter part of travel of the bag about the axis of the movable member s.

As each bag 3 passes beyond the trailing edge of the plate 25 under rotation of the movable member 4, the side wall forming plate 6 of the compartment '1 in which the bag is contained is permitted to move laterally outwardly, thus releasing the bag 3 which engages a platform 26 that is pivotally mounted on the outer ends of a pair of parallel arms 2'5, the inner ends of which are pivotally secured to a bracket 28 mounted on the frame I. A coil tension spring 25 biases the platform 26 in a generally upstanding direction toward the rotary member 1. However, the weight of a filled bag 3 is sufiicient to overcome the bias exerted by the spring 28 and, when the filled bag 3 engages the platform 2%, said platform lowers to deposit the bag 3 gently on the upper operative flight 36 of an endless belt conveyor 3!. It should here be noted that the arcuate pressure plate 25 is mounted on the upper end of the bracket 23 by a suitable mounting element 25', and that the platform 25 maintains the freshly pasted bag sealed until the bag is deposited on the conveyor 31.

The above-described elements comprise a bag closing and sealing machine which is more fully disclosed in the United. States patents to Belcher, above identified, and a co-pending application for United States patent filed December 1, 1950, by Harold V. Kindseth, Serial No. 198,663, and entitled Bag Supporting Means for Bag Closing and Sealing Machines, and now Patent No. 2,599,393. In view of the above disclosures, it is not deemed necessary to describe the foregoing in greater detail herein.

The endless conveyor belt 3! runs over a pair of pulleys 32 and 33 mounted on shafts 34 and 35 respectively that are journalled in suitable bearing brackets 36 and 3'! on the frame structure I. A portion of the belt 31 underlies the rotary member 6 so as to receive a filled bag 3 therefrom, in an inverted position. The bags 3 are supported in an upright position, when directed to the conveyor 3!, by a pair of laterally spaced upstanding guide plates or the like 38 and laterally spaced pairs of guide belts 39 and ill each running over pulleys i! and 52 fast on shafts 33 and M respectively journalled in suitable bearings 55 and 46 respectively carried by the frame structure l. The guide belts 39 and ii] of each pair thereof are driven from the shaft 3 3 of the conveyor belt pulley 32 by means of an endless link chain 57 running over a sprocket wheel 48 fast on the shaft 3 3 and another sprocket wheel as mounted fast on a shaft 59 which is suitably journalled in a bearing bracket 55 and. an endless belt 52 running over a pulley 53 fast on the shaft and another pulley 55 mounted fast on the shaft M at right angles to the shaft 553. With reference to Fig. 3, it will be seen that each of the pairs of guide belts 39 and Ml are independently riven from the shaft 34 by identical chains and belts M and 52 respectively.

The inverted, closed, and sealed bags 3 are directed by the delivery conveyor ill at a point or station remote from the movable member 4 to a second delivery conveyor 55. The conveyor 55 may be of any suitable type, but preferably and as shown, is of the conventional endless belt variety comprising a supporting frame 55 and an endless belt 5! running over suitable spaced pulleys or the like 58, one of which is shown. The conveyor belt 5? delivers the bags to a suitable point where the bags are packed in cartons or otherwise prepared for storage or shipment, and is driven at a considerably lower speed than the normal speed of the first delivery conveyor belt 3|. When a closed and sealed bag is deposited onto the upper fiight 30 of the conveyor belt 3! from its compartment 7, the bag must be moved by the conveyor 3! at a rate of speed sufiicient to avoid its being upset by any projecting part of the constantly rotating movable member 5 such as for instance the adjacent compartment end wall member 8. For this reason, the normal speed of the conveyor belt 3! should be at least as great or greater than the peripheral speed of the movable member l. However, when the bag 3 approaches the station at which it is transferred to the conveyor belt 5?, its speed should be retarded to approximately the speed of travel of the belt 5'! so that there is no danger of upsetting the bag at this point. To accomplish this end, v e provide automatic speed change mechanism for driving the first conveyor belt 3! at relatively high speed when a bag 3 is deposited thereon from the movable member s and at a relatively low speed when the bag 3 approaches the second conveyor 55, said mechanism now to be described.

With reference particularly to Fig. 6, it will be seen that the one end of the drive shaft l5 projects outwardly from the frame structure i and has keyed or otherwise rigidly secured thereto mounting means in the nature of a flange 59. Journalled on the shaft 16 for rotation relative thereto is a sleeve which is formed at its inner end adjacent the flange 59 to provide a driven element in the nature of a pinion or sun gear 6i. A drive wheel or sprocket 62 is telescoped over the outer end portion of the sleeve 60 and has locked thereto for common rotary movement a key or the like 63. The sprocket 62 is provided with an axially outwardly projecting hub 68 which at its outer end is formed to pro vide a recess for the reception ofa conventional overrunning clutch 66. The clutch 85 comprises an inner member 57, a cooperating outer member 68, and a plurality of rollers or the like 69 which engage outer and inner surfaces of the members Bl and 68 respectively. The inner member 5'! is keyed to the outer reduced end '10 of the drive shaft It, as indicated at H, and held against axial movement by washer l2 and a lock washer-equipped nut "53 screw-threaded on the reduced end it of the shaft l6. The outer member 68 engages the side wall of the recess 65 with a press fit to be rotatable therewith. Obviously, with this arrangement, the drive shaft I6 is operative to rotate the sprocket wheel 62 but permits free Wheeling of the sprocket wheel 52 at speeds greater than the speed of rotation of the shaft it in the same direction for a purpose which will hereinafter become apparent. A flanged collar '54 is journalled on the sleeve 68 intermediate the sun gear 6| and the sprocket wheel 52 by means of antifriction bearings and has anchored to its outer peripheral portion, by means of bolts or the like 16, a driven element in the nature of a ring gear Tl concentric with the sun gear (ii. A plurality,

as shown 3, of planet gears 78 are journalled for U rotation on circumferentially spaced stuo shafts l9 and have intermeshing engagement with the sun gear El and the ring gear ll. The stub shafts 79 are rigidly secured to the flange 59 by means of lock washer-equipped nuts or the like 80, one of which is shown.

The mechanism immediately above described is one form of an epicyclic train which, for the purpose of the present example, comprises what is known as a type of planetary transmission. With the arrangement shown, if the collar l l and ring gear 71 are permitted to rotate freely, the sleeve 6% will tend to rotate at the same speed as that of the shaft l6. However, any load placed upon the sprocket wheel 52 will tend to reduce the speed of the sleeve til whereupon the sprocket wheel 62 will be driven by the drive shaft it through the overrunning clutch 656. It should here be noted that the sprocket Wheel 52 forms the driver for the first delivery conveyor 3! and is connected thereto by driving connections including an endless link chain or belt running over said sprocket wheel 62 and one of a pair of connected idler sprockets 32 journalled on a stub shaft 83 secured to the frame structure l, and a second endless link chain or belt 84 running over the other of said pair of sprockets 82 and a driven sprocket 85 keyed or otherwise anchored to the shaft 34 of the first delivery conveyor.

If, at any time during rotation of the shaft H5 and the parts carried thereby, the collar 74 and ring gear 17 carried thereby should be locked against rotation, rotary movement of the flange 59 will be transferred through the planet gears 18 to the sun gear 6i and sleeve 63 at a greater speed than that of: the shaft 55. Consequently, the drive wheel sprocket 62 together with the first delivery conveyor 3i will be driven at a greater speed than formerly. Means for period.- ically locking the collar It and ring gear 7'! against rotary movement for predetermined intervals and releasing the same for rotation comprises a pair of diametrically opposed abutments 86 and 87 extending radially outwardly from the periphery of the collar 14, a stop element 88, and a cam 89 for moving the stop element 88 out of the path of travel of the abutment members 86 and 87 and permitting return thereof into the path of travel of said abutments at predetermined intervals. The stop element 83 is in the nature of a head on one end portion of a slide rod 9i? carried by a rock arm 9| pivotally mounted to the frame structure I, as indicated at 92. A. guide bracket 93 has an inturned portion 94 at its outer end, see Fig. 7, which forms the base of reaction for one of a pair of cushioning springs 85 which engage adjustable collars 96 on the slide rod 96 and cushion the impact of the abutments t6 and Bl against the stop element or head 88. The free end of the rock arm 9| is provided with a bearing boss 91 which supports a cam follower roller 98 that lies in the plane of the cam 89 and engages the same. Said cam 88 is formed to provide a relatively short circumferentially extended stop element releasing portion 99 and a relatively long circumferentially extended portion its which, when engaged by the cam follower roller 98 permits the stop element 38 to enter the path of travel of the abutments B5 and 87. We further provide yielding means in the nature of a coil tension spring ifil anchored at one end to a crank-acting portion 502 integrally formed with the rock arm 9! and at its other end to the frame 5, as indicated at 33, see Fig. 1. The cam 89 is rigidly secured to the flange 59 by circumferentially spaced bolts HM, one of which is shown, see Fig. 6. The bolts Hid are provided with clamping washers I and permit adjustment of the cam 39 circumferentially with respect to the drive shaft [6.

The high portion 99 of the cam $9 is so positioned on the flange 59 so that when a closed and sealed bag 3 is being deposited on the operative flight 36 of the first conveyor belt 3!, the stop element or head 88 is positioned to engage one of the abutments 868l. As above indicated, this engagement will cause the conveyor belt 3! to run at its normal relatively high speed as the bag :5 is deposited thereon. Preferably, the arrangement is such that the speed of linear travel of the conveyor belt 3i is approximately onefourth greater than the peripheral speed of the rotary member l. Hence, the bag 3 is quickly moved out of the path of travel of any portion of the rotary member which might otherwise come into contact with and upset the same. As the bag approaches the end of the operative flight at which point it will be transferred to the relatively slow conveyor belt 57, the high portion $9 of the cam 89 engages the cam follower roller 98, moving the stop element 88 out of engagement with the adjacent abutment. This action permits rotary movement of the collar i l and the ring gear EC and causes the sprocket wheel 62 to be driven through the overrunning clutch it at relatively low speed, said low speed being approximately that of. the second conveyor belt 57. As soon as the cam 89 permits return of the stop element 38 into the path of travel of one of the abutments 8% and 87, under bias of the spring it i, the resultant engagement of one of the abutments with the stop element will again cause the drive wheel or sprocket 52 to be driven through the sun gear 5! at relatively high speed to convey the next bag 3 away from the movable or rotary member The slow movement of the second conveyor provides ample time for the adhesive used in sealing the bags to set while the bags are in an inverted position thereon. In the event that a relatively quick drying adhesive is used and that the second conveyor belt 51 is operated at a greater speed, the spring H)! can be disconnected from the lever arm 1 532, thus permitting the rock arm 9! to swing under the action of gravity to a point where the stop element 83 is permanently removed from the path of travel of the abutments 853 and 8'1. However, the downward swinging movement of the rock arm 9 l under the action of gravity, will move the extreme upper end H32 of the crank-acting portion 462 into the path of travel of the abutments and, upon engagement thereof, will place the epicyclic train in condition to drive the con-' veyor belt 3! at constant high speed unaffected by rotation of the cam 89.

Our invention has been thoroughly tested and found to be completely satisfactory for the accomplishment of the objectives set forth; and, while we have shown and described a preferred embodiment of our novel mechanism, it will be understood that the same is capable of modification as to structure and arrangement of parts without departure from the spirit and scope of the invention, as defined in the claims.

What we claim is:

1. Automatic speed change transmission mechanism for delivery conveyors or the like, said mechanism comprising a frame, a power driven shaft journalled for rotation in said frame, a drive wheel, overrunning clutch means coupling the drive wheel to said shaft, an epicyclic train including a driving gear carried by the drive shaft and a pair of driven gears in meshing engagement with said driving gear, one of said driven gears being secured to the drive Wheel for common rotation therewith, the other of said driven gears being rotatable on the axis of said drive shaft, and mechanism for periodically locking said other driven gear against rotation for predetermined intervals and releasing the same, whereby the drive wheel is rotated by said one of the drive gears when said other driven gear is locked against rotation, said drive wheel being driven by the drive shaft through said overrunning clutch means responsive to release of said other driven gear, said locking and releasing mechanism comprising an abutment carried by said other driven gear, a stop element mounted on the frame for movements into and out of the path of travel of said abutment and biased toward engagement therewith, and mechanism responsive to rotation of the drive shaft to move said stop element out of the path of travel of said abutment against said bias during predetermined rotary movement of the drive shaft and to permit movement of the stop element into the path of travel of said abutment during other predetermined rotary movement of the drive shaft.

2. Automatic speed change transmission mechanism for delivery conveyors or the like, said echanism comprising a frame, a power driven aft iournalled for rotation in said frame, a drive wheel, overrunning clutch means coupling the drive wheel to said shaft, an epicyclic train including a driving gear carried by the drive shaft and a pair of driven gears in meshing engagement with said driving gear, one of said driven gears being secured to the drive wheel for common rotation therewith, the other of said driven gears being rotatable on the axis of said drive shaft, and mechanism for periodically locking said other driven gear against rotation for predetermined intervals and releasing the same, whereby the drive wheel is rotated by said one of the driven gears when said other driven gear is locked against rotation, said drive wheel being driven by the drive shaft through said overrunning clutch means responsive to release of said other driven gear, said locking and releasing mechanism comprising an abutment carried by said other driven gear, a stop element mounted on the frame for movements into and out of the path of travel of said abutment and biased toward engagement therewith, and cam means mounted for common movement with the driving gear on the drive shaft and operative to move said stop element out of the path of travel of said abutment against said bias during predetermined rotary movement of the drive shaft and permitting movement of the stop element into the path of travel of said abutment during other predetermined rotary movement of the drive shaft.

3. Automatic speed change transmission mechanism for delivery conveyors or the like, said mechanism comprising a frame, a power driven shaft journalled for rotation in said frame, a drive wheel, overrunning clutch means coupling the drive wheel to said shaft, an epicyclic train including a driving gear carried by the drive shaft and a pair of driven gears in meshing engagement with said driving gear, one of said driven gears being secured to the drive wheel for common rotation therewith, the other of said driven gears being rotatable on the axis of said drive shaft, and mechanism for periodically locking said other driven gear against rotation for predetermined intervals and releasing the same, whereby the drive wheel is rotated by said one of the drive gears when said other driven gear is locked against rotation, said drive wheel being driven by the drive shaft through said overrunning clutch means responsive to release of said other driven gears, said locking and releasing mechanism comprising an abutment carried by said other driven gear, a stop element, means mounting the stop element on said frame for movements into and out of the path of travel of said abutment, yielding means biasing the stop element toward said path of travel of the abutment, and mechanism responsive to rotation of the drive shaft to move said stop element out of the path of travel of the abutment during predetermined rotary movement of the drive shaft and to permit the bias of said yielding means to move the stop element into the path of travel of said abutment during other predetermined rotary movement of the drive shaft.

4. The structure defined in claim 3 in which said last-mentioned mechanism comprises a cam carried by the drive shaft for common rotary movement therewith and a cooperating cam follower carried by the mounting means for said stop element.

5. In a machine for closing and sealing filled bags, a movable member having therein a compartment for holding a filled bag during the closing and sealing thereof, a conveyor for the reception of a closed and sealed bag from said compartment and delivery of said bag to a station remote therefrom, means for imparting 0perative movements to said movable member and including a drive shaft, and means coupled to said drive shaft for imparting delivery movements to said conveyor at a given speed when receiving a bag from the movable member and at a different speed when the bag approaches said station, said last-mentioned means comprising a drive wheel, overrunning clutch means coupling the drive wheel to the drive shaft, driving connections between the drive wheel and the conveyor, and an epicyclic train including a driving gear carried by the drive shaft and a pair of driven gears in meshing engagement with the driving gear, one of said driven gears being secured to the drive Wheel for common rotation therewith, the other of said driven gears being rotatable on the axis of said drive shaft, and mechanism for periodically locking said other driven gear against rotation for predetermined intervals and releasing the same, whereby the drive wheel is rotated by said one of the driven gears when said other driven gear is locked against rotation said drive wheel being driven by the drive shaft through said overrunning clutch means responsive to release of said other driven gear, said locking and releasing mechanism comprising an abutment carried by said other driven gear, a stop element mounted on the frame for movements into and out of the path of travel of said abutment and biased toward engagement therewith, and mechanism responsive to rotation of the drive shaft to move said step element out of the path of travel of said abutment against said bias during predetermined rotary movement of the drive shaft and to permit movement of the stop element into the path of travel of said abutment during other predetermined rotary movement of the drive shaft.

6. In a machine for closing and sealing filled bags, a movable member having therein a compartment for holding a filled bag during the closing and sealing thereof, a conveyor for the reception of a closed and sealed bag from said compartment and delivery of said bag to a station remote therefrom, means for imparting operative movements to said movable member and including a drive shaft, and means coupled to said drive shaft for imparting delivery movements to said conveyor at a given speed when receiving a bag from the movable member and at a different speed when the bag approaches said station, said last-mentioned means comprising a drive Wheel, overrunning clutch means coupling the drive wheel to the drive shaft, driving connections between the drive wheel and the conveyor, and an epicyolic train including a driving gear carried by the drive shaft and a pair of driven gears in meshing engagement with the driving gear, one of said driven gears being secured to the drive wheel for common rotation therewith, the other of said driven gears being rotatable on the axis of said drive shaft, and mechanism for periodically locking said other driven gear against rotation for predetermined intervals and releasing the same, whereby the drive wheel is rotated by said one of the driven gears when said other driven gear is locked against rotation, said drive wheel being driven by the drive shaft through said overrunning clutch means responsive to release of said other driven gear, said locking and releasing mechanism comprising an abutment carried by said other driven gear, a stop element, means mounting the stop element for movements into and out of the path of travel of said abutment, yielding means biasing the stop element toward said path of travel of the abutment, and mechanism responsive to rotation of the drive shaft to move said step element out of the path of travel of the abutment during predetermined rotary movement of the drive shaft and to permit the bias of said yielding means to move the stop element into the path of travel of the abutment during other predetermined rotary movement of the drive shaft.

7. The structure defined in claim 6 in which said last-mentioned mechanism comprises a cam carried by the drive shaft for common rotary movement therewith and a cooperating cam follower carried by the mounting means for said stop element.

8. In a machine for closing and sealing filled bags, a movable member having therein a compartrnent for holding a filled bag during the closing and sealing thereof, a conveyor for the reception of a closed and sealed bag from said compartment and delivery of said bag to a station remote therefrom, means for imparting operative movements to said movable member and including a drive shaft, and means coupled to said drive shaft for imparting delivery movements to said conveyor at a given speed when receiving a bag from the movable member and at a different speed when the bag approaches said station, said last-mentioned means comprising a drive wheel, overrunning clutch means couplin the drive wheel to the drive shaf driving connections between the drive wheel and the conveyor, an epicyclic train including a driving gear carried by the drive shaft and a pair of driven gears in meshing engagement with said driving gear, one of said driven gears being secured to the drive wheel, the other of said driven gears being rotatable on the axis of said drive shaft, and mechanism for periodically locking said other driven gear against rotation for predetermined intervals, whereby the drive wheel is rotated by said one of the driven gears, said drive wheel being driven by the drive shaft through said overrunning clutch means responsive to release of said other driven gear for free rotation, said last-mentioned mechanism comprising an abutment carried by said other gear, a stop element movable into and out of the path of travel of said abutment and biased toward engagement therewith, and cam means mounted for common movement with said driving gear on the drive shaft and operative to move said stop element out of the path of travel of said abutment against said bias during predetermined rotary movement of the drive shaft and permitting movement of the stop element into the path of travel of said abutment during other predetermined rotary movement of the drive shaft.

9. Automatic speed change transmission mechanism for delivery conveyors or the like, said mechanism comprising a frame, a power driven shaft journailed for rotation in said frame, a drive wheel, overrunning clutch means coupling the drive wheel to said shaft, an epicyclic train including a driving gear carried by the drive shaft and a pair of driven gears in meshing engagement with said driving gear, one of said driven gears being secured to the drive wheel for common rotation therewith, the other of said driven gears being rotatable on the axis of said drive shaft, and mechanism for periodically locking said other driven gear against rotation for predetermined intervals and releasing the same, whereby the drive wheel is rotated by said one of the driven gears when said other driven gear is locked against rotation, said drive wheel being driven by the drive shaft through said overrunning clutch means responsive to release of said other driven gear, said mechanism for locking said other driven gear comprising a stop element and an abutment element one mounted on said other gear and the other on said frame, yielding means biasing one of said elements toward engagement 11 with the other thereof, and means for periodi- Number cally moving said one of the elements away from 1,989,471 operative engagement with the other thereof 2,301,543 against bias of said yielding means. 2,552,246 5 2,605,651 References Cited in the file of this patent UNITED STATES PATENTS Number Number Name Date 93 212 1,109,259 Sons Sept. 1, 1914 10 Name Date Belcher Jan. 29, 1935 Hlavaty Nov. 10, 1942 Wilckens May 8, 1951 Winther Aug, 5, 1952 FOREIGN PATENTS Country Date Germany July 4, 1940 

